Why Do Antibiotics Exist?

mBio. 2021 Dec 21;12(6):e0196621. doi: 10.1128/mBio.01966-21. Epub 2021 Dec 7.

Abstract

In the struggle with antibiotic resistance, we are losing. There is now a serious threat of moving into a postantibiotic world. High levels of resistance, in terms of both frequency and strength, have evolved against all clinically approved antibiotics worldwide. The usable life span of new clinically approved antibiotics is typically less than a decade before resistance reaches frequencies so high as to require only guarded usage. However, microbes have produced antibiotics for millennia without resistance becoming an existential issue. If resistance is the inevitable consequence of antibiotic usage, as has been the human experience, why has it not become an issue for microbes as well, especially since resistance genes are as prevalent in nature as the genes responsible for antibiotic production? Here, we ask how antibiotics can exist given the almost ubiquitous presence of resistance genes in the very microbes that have produced and used antibiotics since before humans walked the planet. We find that the context of both production and usage of antibiotics by microbes may be key to understanding how resistance is managed over time, with antibiotic synthesis and resistance existing in a paired relationship, much like a cipher and key, that impacts microbial community assembly. Finally, we put forward the cohesive, ecologically based "secret society" hypothesis to explain the longevity of antibiotics in nature.

Keywords: antibiotic resistance; community assembly; cooperation; evolution.

Publication types

  • Historical Article
  • Research Support, N.I.H., Extramural
  • Review

MeSH terms

  • Animals
  • Anti-Bacterial Agents / biosynthesis
  • Anti-Bacterial Agents / history
  • Anti-Bacterial Agents / pharmacology*
  • Bacteria / drug effects*
  • Bacteria / genetics
  • Bacteria / metabolism*
  • Bacterial Infections / drug therapy
  • Bacterial Infections / history
  • Bacterial Infections / microbiology
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Drug Resistance, Bacterial*
  • History, 20th Century
  • History, 21st Century
  • Humans

Substances

  • Anti-Bacterial Agents
  • Bacterial Proteins